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Problem with object picking and modified camera backbuffer matrix

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EgonOlsen:
Strange...i don't see why it shouldn't work that way assuming that the rotation matrix doesn't contain the translation anymore when setting it.
If nothing else helps, you can try to do the projection into world space on your own based on the combined matrix. The reason why it doesn't work with the combined matrix is most likely that reproject2D3DWS treats the matrix as a 3x3 matrix for performance reasons. You can try


--- Code: ---public SimpleVector reproject2D3DWS(Camera camera, FrameBuffer buffer, int x, int y, SimpleVector toFill) {
SimpleVector ray = reproject2D3D(camera, buffer, x, y, VIEWPLANE_Z_VALUE, toFill);
ray.matMul(camera.getBack().invert());
return ray;
}

--- End code ---

instead. However, the clean solution would be to separate the two transformations...

redfalcon:
Just that I get it right:
What should I use for VIEWPLANE_Z_VALUE, the far clipping plane?

--- Code: ---
//...
public SimpleVector reproject2D3DWS(Camera camera, FrameBuffer buffer, int x, int y, SimpleVector toFill) {
SimpleVector ray = Interact2D.reproject2D3D(camera, buffer, x, y, 2000, toFill);
ray.matMul(camera.getBack().invert());
return ray;
}

public void findNearestObject(int touchX, int touchY) {

SimpleVector dir = reproject2D3DWS(camera, frameBuffer, touchX, touchY, new SimpleVector()).normalize();
Object[] res = world.calcMinDistanceAndObject3D(camera.getPosition(), dir, 10000);
              //...
}


--- End code ---

Is that correct?

EgonOlsen:
No, just use 1f.

redfalcon:
No Luck, that doesn't work either :/

I tried a different approach, and set the GL-Matrix as the rotation matrix of my model. This works fine for placement and picking, but now the rotations (With object.rotateX()) rotate around an axis which seems to be far above the object (so it's pretty unusable). Which is normal I guess, since I modified the rotation matrix. Is there a way to get a proper axis that I can use with rotateAxis() or the like?

EgonOlsen:
If you use a combined matrix as rotation matrix, you'll change the rotation pivot by this translation. The new rotation pivot should be the negative translation.

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